But first, think about what’s in your glass. . .

Researchers are reconsidering the long-held belief that light-to-moderate drinking is beneficial.

For many people, alcohol is part of their social, business, and family lives; an enjoyable and traditional accompaniment to food and celebration. People’s strong feelings and beliefs regarding alcohol reflect cultural, religious, geographical, and sociological influences. Muslims, Mormons, and certain Christians forbid alcohol consumption, while other religions take a more permissive approach and even incorporate it into rituals.

Throughout history, humans’ relationship with alcohol has been mixed; some revere it as a health elixir, others dread it as an addictive drug. The latter group claimed victory when the U.S. enacted Prohibition in January 1920, outlawing alcohol with the passage of the 18^th Amendment to the U.S. Constitution. The former celebrated when the government repealed Prohibition with the 21^st Amendment in December 1933. Today, the alcohol industry plays a vital part in the U.S. economy – responsible for more than 16 percent of all beverage sales.

Now, researchers are reconsidering the long-held belief that light-to-moderate drinking is beneficial. A few recent studies and analyses give reasons to be skeptical about any health benefits of alcohol.

What is alcohol?

Alcohol distilleries take many forms.

In chemistry, an alcohol is any organic compound where the hydroxyl functional group, [-OH], binds to carbon [C]. Alcohol’s chemical formula is C₂H₅OH, where the C₂H₅ represents the ethyl group linked to the hydroxyl group, -OH. Ethyl alcohol often is abbreviated as EtOH. It is a psychoactive substance and the principal type of alcohol found in alcoholic drinks.

Ethanol is naturally produced when sugars are fermented by yeasts or via petrochemical processes. It also has medical applications as an antiseptic and disinfectant, and is widely used as a chemical solvent, either for scientific chemical testing or in synthesis of other organic compounds in manufacturing. Ethanol also is used as a clean-burning fuel source, i.e., E85 – an ethanol fuel blend of 85 percent ethanol fuel (mostly from corn) and 15 percent gasoline by volume.

Use and misuse

Only about 35 percent of American adults drink no alcohol. Some 55 percent are light or moderate drinkers and 10 percent drink more than moderately. Alcohol is estimated to cause 90,000 deaths per year in the U.S., directly or indirectly, including more than 11,000 traffic fatalities and thousands of other fatal injuries. What’s more, alcohol-related deaths occur mostly among the relatively young, shortening lives by an average of 30 years. Treating alcoholism costs billions annually.

Alcohol abuse – a psychiatric diagnosis of recurring harmful use of alcohol – is now officially referred to as alcohol use disorder (AUD), or alcohol dependence. AUD manifests in people in two ways: Drinkers who have anti-social and pleasure-seeking tendencies, and drinkers who forgo alcohol for long periods of time but are unable to control themselves once they start.

A standard drink

Many people are surprised to learn what counts as a standard drink. The amount (volume) of liquid in a glass, can, or bottle does not reflect how much alcohol is consumed. Different types of beer, wine, or malt liquor can have very different amounts of alcohol content per liquid volume consumed.

In the United States, one “standard” drink contains roughly 14 grams (0.6 fl oz) of pure alcohol, which is found in:

• 12 ounces of regular beer, about 5 percent alcohol
• 5 ounces of wine, about 12 percent alcohol
• 1.5 ounces of distilled spirits, about 40 percent alcohol

The image below shows examples of one standard drink of “pure” alcohol. Of course, the percent of pure alcohol, expressed as alcohol by volume (alcohol/vol), varies within and across beverage types and may not reflect customary serving sizes.

Beer 12 fl. oz.	Malt Liquor 8-9 fl. oz.	Table wine 5 fl. oz.	Fortified wine (sherry, port) 3-4 fl. oz.	Cordial, aperitif 2-3 fl. oz.	Brandy, cognac 1.5 fl. oz. (shot)	Distilled spirits (80 proof) 1.5 fl. oz. (shot)
~5 percent	~7 percent	~12 percent	~17 percent	~24 percent	~40 percent	~40 percent

History

In 1867, archaeologists unearthed the oldest known liquid wine from a site near the city of Speyer, Germany.

Discovery of jugs dating to the late Stone Age suggest that people began to ferment beverages as early as 10,000 BC. Researchers discovered an alcoholic drink made of rice, grapes, honey, and hawthorn berries dated from around c. 7000-6500 BC and in the Chinese village of Jiahu in the Henan province. In 1867, archaeologists unearthed the oldest known liquid wine from a site near the city of Speyer, Germany. Experts dated the liquid to 350 AD, and believed it belonged to a Roman noble who was buried with the bottle (liquid and all).

Sumerian and Egyptian texts dating from around 2100 BC mention the medicinal use of alcohol, and the Hebrew Bible recommends giving alcoholic drinks to the depressed and dying to alleviate their misery (Proverbs 31:6-7).

In classical Greece, people drank wine at breakfast and other gatherings, and in the 1^st century BC most Roman citizens considered wine as part of their regular diet. Both the Greeks and the Romans generally drank diluted wine (the strength varying from 1-part wine and 1-part water, to 1-part wine and 4-parts water).

In Europe during the Middle Ages, all classes and ages of people drank beer – often of very low strength – every day. Even nuns had an allowance of six pints of ale each day, according to documents from the time.

By the time the Europeans reached the Americas in the 15^th century, several native civilizations had developed alcoholic beverages. According to a post-conquest Aztec document, the local “wine,” called pulque, generally was consumed during religious ceremonies. But citizens over the age of 70 had unfettered access to the drink.

The natives of South America produced a beer-like beverage from maize (corn), which they chewed before fermentation in order to turn the starch into simple sugar. In ancient Japan, natives used this chewing technique to produce sake from rice.

Archaeologists found chemical evidence of wine, dating back to 6000-5800 BC (the early Neolithic period), in residues from ancient pottery excavated near Georgia, in the Middle East. Wine has a long history of medicinal use, with healers recommending it as a safe alternative to drinking water, an antiseptic for treating wounds, a digestive aid, and as a cure for wide-ranging ailments including lethargy, diarrhea, and pain from childbirth. Wine continued to play a major role in medicine until the late-19^th and early-20^th centuries, when changing opinions and medical research cast doubt on its role as part of a healthy lifestyle.

On the rocks

A typical Prohibition poster of the time.

Even after ratification of the 18^th Amendment in 1920, whiskey drinkers could obtain product by way of prescription from a medical doctor. Pharmacists were amenable to the process – and “patients” consumed more than a million gallons per year through alcohol prescriptions.

Because Prohibition banned only the manufacturing, sale, and transport – but not possession or consumption – of alcohol, some people and institutions who had bought or made liquor prior to the passage of the 18^th Amendment continued to serve it legally. With each passing year, the number of repeal organizations increased and demand for repeal intensified. In 1932, the Democratic Party’s platform included a promise to repeal Prohibition, and presidential candidate Franklin D. Roosevelt highlighted the issue in his campaign. By then, about three-quarters of American voters and an estimated 46 states favored repeal. In 1933, the 21^st Amendment repealed the 18^th Amendment; nevertheless, almost two-thirds of the states adopted some form of local prohibition. By 1966 (that’s right 1966!), all states had finally repealed state-level Prohibition laws.

Alcohol is hard to study

Most alcohol research relies on cross-sectional, observational studies that follow groups of drinkers and nondrinkers for a period of time to compare their health statuses. Observational research is valuable, but not definitive in proving cause and effect. One potential “confounder” in observational studies is that nondrinkers, as a group, include many people who gave up alcohol for health reasons — dubbed the “sick-quitter effect.” Researchers try to mitigate this effect by adjusting the data in various ways, but it’s difficult to do so completely. [This problem was addressed in 2016 in an analysis of 87 studies, published in the Journal of Studies on Alcohol and Drugs. This research found that any “apparent” reduced mortality rate among light-to-moderate drinkers was eliminated when the comparison group was limited to lifelong abstainers or occasional drinkers (i.e., no former drinkers).]

It’s nearly impossible to undertake randomized clinical trials on alcohol, which could establish causality, as it would involve telling hundreds or thousands of individuals to stop or start drinking for months or years. This has never been done before, until now.

The National Institutes of Health (NIH) has proposed an ambitious new study – “The Moderate Alcohol and Cardiovascular Health Trial (MACH15),” a multicenter, worldwide, randomized clinical trial comparing ~15 gm (0.53 oz) of daily alcohol versus abstention among 7,800 participants, aged 50 years and older with advanced cardiovascular risk. Intervention will average six years with a common end date. Following recruitment and pre-screening, participants will attend a screening visit followed by a two-week abstention-washout period, a baseline visit and randomization, and subsequent visits at three, six, and 12 months the first year, and then annually until the end. Results are a long way off, and they’re still unlikely to answer all questions about alcohol and heart health, but the study is a step in the right direction.

A confusing message

Research on alcohol consumption and health over the last three decades is certainly confusing. The global alcohol industry (Big Alcohol) is much like the industries supporting tobacco, sugar, meat, and processed foods. Its leaders have waged a sophisticated (and successful) campaign by sponsoring intergovernmental events, funding educational initiatives and research, and supporting sports and cultural events aimed to undermine perceptions of alcohol’s related health problems. The major aim of Big Alcohol, which has seized control of the public relations battle with the public health community, is to perpetuate myths regarding alcohol’s positive effects, spread doubt about negative scientific evidence, and pressure lawmakers to refrain from introducing any regulations.

The key argument supporting alcohol’s benefits centers on promoting and advertising the idea of a balanced approach to health benefits versus any risks of consumption. Big Alcohol consistently reminds people to be “responsible” drinkers, supporting the erroneous idea that “moderate” or “light” drinkers experience no harm, and even can gain some benefits compared to heavy drinkers. They have convinced most people, including many in the medical community, that it is only heavy drinkers that shouldn’t be drinking. The medical community at large and government policymakers apparently accept the idea that drinking in moderation is OK, and maybe could even be healthy. This could explain why regulations or interventions regarding the global supply of alcohol are so minimal. Warning labels on alcohol containers might undermine or contradict any possible health benefits of alcohol or, worse yet, anger the Big Alcohol lobby.

Alcohol and health outcomes

Research on alcohol use and its effects is more difficult than it seems.

New and updated research analyses call into question the wisdom of “responsible drinking” as a way to promote positive health. When researchers re-analyze the data used to show positive health effects of alcohol by removing the systematic error of misclassifying former drinkers as if they were lifelong abstainers, the data clearly show that moderate alcohol consumption, like a glass of wine a day, is not cardio-protective. In fact, the death-versus-alcohol relationship reveals a consistent straight line — linear dose response — meaning more alcohol, more death with no protection at low levels of use.

In previous observational (population) studies, individuals who had quit drinking often were misclassified as nondrinkers. Classified as nondrinkers, these former moderate-to-heavy drinkers confound any relationship between alcohol and positive health. The inaccurate designation creates misleading conclusions. These former drinkers, for example, as a group, may be more likely to drink a glass of wine with a salad than a cheeseburger, and that’s why the wine might appear as promoting good health.

A recent study found even one drink a day can be “cardiotoxic.”

In an attempt to provide reliable evidence on the cause-and-effect relationship between exposures and risks of disease, researchers have developed new analyses techniques, sometimes taking into consideration genetic differences between individuals. For example, data show that alcohol raises an individual’s HDL (good) cholesterol. But, unfortunately, re-analysis of these data show that good cholesterol doesn’t lower heart disease risk in individuals with genetically elevated HDL levels. Eliminating such confounding effects of genetic differences between individuals makes it possible to gain greater insight on the effects of alcohol, per se.

Remarkably, it is possible to study people who are genetically predisposed not to drink alcohol. These individuals are born with variants of the enzyme acetaldehyde, which causes unpleasant alcohol experiences from nausea to flushing sensations. These individuals are born less likely to drink then those with a normal acetaldehyde-alcohol response. So, do these genetic nondrinkers have an increased risk of heart disease, like the original observational studies indicated? No! It’s just the opposite. Genetic nondrinkers, and presumably those who drink little or no alcohol – have a reduced risk of heart disease. This suggests reduction of alcohol consumption, even for light-to-moderate drinkers, benefits cardiovascular health. This is just the opposite of what Big Alcohol and their supporters would want us to believe.

Other data show those with the lowest alcohol consumption experience the least health risks. For example, those who completely abstain from alcohol are at the lowest risk of subclinical markers of atherosclerosis, like thickening of the carotid arteries and coronary calcium scores. Also, alcohol increases blood pressure, which raises cardiac risk. A recent study found even one drink a day can be “cardiotoxic” and increase the risk of atrial fibrillation and enlargement of one of the heart’s chambers. That risk rises with each daily drink.

So, to drink or not to drink?

What conclusions can we draw from the emerging evidence on alcohol and health?

First, health advice should come from health authorities, not from Big Alcohol. I believe Big Alcohol should remove all misleading references to purported health benefits of alcohol. Second, alcohol is an intoxicating, addictive, toxic, and potentially carcinogenic drug, and should not be recommended as a therapeutic-medicinal agent. There are better ways to positively influence health outcomes – namely diet and exercise (and drugs when necessary). Unlike alcohol, interventions like diet and exercise pose little or no abuse potential.

References

• Braillon, A. “Consumption of alcohol, an addictive carcinogen, cannot be a healthy lifestyle choice!” Journal of Studies on Alcohol Drugs. 2016;77(5):838.
• Burki, T.K. “Low public awareness of the link between cancer and alcohol.” Lancet Oncology. 2016;17(5):e184.
• Chikritzhs, T., et al. “Has the leaning tower of presumed health benefits from ‘moderate’ alcohol use finally collapsed?” Addiction. 2015;110(5):726-727.
• Connor, J. “Alcohol consumption as a cause of cancer.” Addiction. 2017;112(2):222-228.
• Daube, M. “Alcohol’s evaporating health benefits.” BMJ. 2015;350:h407.
• Goulden, R. “Moderate alcohol consumption is not associated with reduced all-cause mortality.” American Journal of Medicine. 2016;129(2):180-186.e4.
• Moodie, A.R. “Big alcohol: The vector of an industrial epidemic.” Addiction. 2014;109(4):525-526.
• Sellman, D. “Ten things the alcohol industry won’t tell you about alcohol.” Drug and Alcohol Review. 2010;29(3):301-303.
• Slevin, T., Chikritzhs, T. “Why is alcohol cancer’s best-kept secret?” Addiction. 2017;112(2):229-230.
• Stockwell, T., Naimi, T. “Study raises new doubts regarding the hypothesized health benefits of ‘moderate’ alcohol use.” Evidence-Based Medicine. 2016;21(4):156.
• Stockwell, T., Zhao, J. “Alcohol’s contribution to cancer is underestimated for exactly the same reason that its contribution to cardioprotection is overestimated.” Addiction. 2017;112(2):230-232.
• Xi, B., et al. “Relationship of alcohol consumption to all-cause, cardiovascular, and cancer-related mortality in U.S. adults.” Journal of the American College of Cardiology. 2017;70(8):913-922.

This piece was edited after publication to correct an error.